std::shared_ptr

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std::shared_ptr
Template:cpp/memory/shared ptr/sidebar content

Defined in header <memory>
template< class T > class shared_ptr;		(C++11 feature)

std::shared_ptr is a smart pointer that manages an object through a pointer to it. Several shared_ptr objects can link to the same object. It is guaranteed to be destroyed when the last shared_ptr pointing to it is destroyed or reset. The object is destroyed using delete expression or a custom deleter that is supplied along the pointer to the managed object during construction.

Contents 1 Member types 2 Member functions 2.1 Modifiers 2.2 Observers 3 Non-member functions

[edit] Member types

Member type	Definition
element_type	T

[edit] Member functions

(constructor)	constructs new shared_ptr (public member function)
(destructor)	destructs the owned object if no more shared_ptrs link to it (public member function)
operator=	assigns the shared_ptr (public member function)
Modifiers
reset	replaces the managed object (public member function)
swap	swaps the managed objects (public member function)
Observers
get	returns a pointer to the managed object (public member function)
operator* operator->	dereferences pointer to the managed object (public member function)
use_count	returns the number of shared_ptr objects referring to the same managed object (public member function)
unique	checks whether the managed object is managed only by the current shared_ptr instance (public member function)
operator bool	checks if there is associated managed object (public member function)
owner_before	checks whether the managed object precedes managed object of another shared pointer in implementation defined order, i.e. orders the managed objects (public member function)

[edit] Non-member functions

std::swap(shared_ptr) (C++11)	specializes the std::swap() algorithm (function template)
make_shared	creates a shared pointer that manages a new object (function template)
allocate_shared	creates a shared pointer that manages a new object allocated using an allocator (function template)
static_pointer_cast dynamic_pointer_cost const_pointer_cast	applies static_cast, dynamic_cast or const_cast to the type of the managed object (function template)